总体思路是后端向华为云OBS服务器申请授权信息并设置过期时间，后端再将授权信息以Map形式发给前端，前端将文件和授权信息直接发给华为云OBS服务器。

1. 引入依赖

		<dependency><groupId>com.huaweicloud</groupId><artifactId>esdk-obs-java</artifactId><version>3.20.6.1</version></dependency><dependency><groupId>com.huaweicloud</groupId><artifactId>esdk-obs-java-bundle</artifactId><version>3.23.9</version></dependency>

2. 向前端发送授权码

package com.example.meetings.controller;import com.obs.services.ObsClient;
import com.obs.services.model.*;
import org.springframework.web.bind.annotation.*;
import java.text.SimpleDateFormat;
import java.util.*;/*** @ClassName: ObsController* @Description: OBS服务器Controller* @Author: wuhuiju* @Version: 1.0*/
@RestController
@RequestMapping({ "/oss" })
public class HweiYunOBSController {/*** 完整域名为/oss/policy* 返回结果formParams.put("x-obs-acl", "public-read");formParams.put("content-type", "text/plain");formParams.put("accessId", accessId);formParams.put("policy", response.getPolicy());formParams.put("signature", response.getSignature());formParams.put("dir", dir);formParams.put("host", host);*/@CrossOrigin@GetMapping("/policy")public Map<String, Object>  policy() {// 访问IdString accessId = "************************";// 访问密钥String accessKey = "************************";// EndpointString endpoint = "************************";// 填写Bucket名称String bucket = "pic";// 填写Host地址，格式为https://bucketname.endpoint。String host = "https://" + bucket + "." + endpoint;// 设置上传到OSS文件的前缀，可置空此项SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");// 生成文件夹，以日期为文件夹名String dateform = simpleDateFormat.format(new Date());String dir = "pic/" + dateform + "/";// 创建ObsClient实例// 使用永久AK/SK初始化客户端ObsClient obsClient = new ObsClient(accessId, accessKey,endpoint);try {// 生成基于表单上传的请求PostSignatureRequest request = new PostSignatureRequest();// 返回结果Map<String, Object> formParams = new HashMap<String, Object>();// 设置对象访问权限为公共读formParams.put("x-obs-acl", "public-read");// 设置对象MIME类型formParams.put("content-type", "image/jpeg");request.setFormParams(formParams);// 设置表单上传请求有效期，单位：秒request.setExpires(3600);PostSignatureResponse response = obsClient.createPostSignature(request);formParams.put("accessId", accessId);formParams.put("policy", response.getPolicy());formParams.put("signature", response.getSignature());formParams.put("dir", dir);formParams.put("host", host);return formParams;} catch (Exception e) {System.out.println(e.getMessage());}return null;}
}